DESCRIPTION: Temporomandibular disorders (TMD's) are musculoskeletal pain conditions characterized by pain in the muscles of mastication and/or the temporomandibular joint. These pain problems are about twice as common in women as in men in the community, and prevalence peaks during the reproductive years. About 80 percent of patients treated in tertiary care settings are women. The investigators propose a 5-year program of clinical epidemiologic and experimental research to examine the possible interactive influences of hormonal status, other gender factors in pain sensitivity, the presence of non-TMD somatic symptoms and psychological distress on TMD pain in women. Study 1 will assess variations in self report of clinical TMD pain, other physical symptoms and psychosocial state in relation to hormonal status across three consecutive ovulatory menstrual cycles for normally cycling female TMD patients, as well as appropriate comparison groups (male TMD patients, female TMD patients who use oral contraceptives and normally cycling pain-free females controls). Studies 2 and 3 will assess variability in responses to standardized experimental pain stimuli at critical points (menses, ovulatory, mid-luteal and late luteal/premenstrual phases) across three consecutive ovulatory cycles in female TMD cases and appropriate controls, to ascertain the extent to which variability and level of pain experience may be attributable to female gender, hormonal status, experience of pain during the menstrual period (i.e., dysmenorrhea) and/or presence of clinical TMD pain. Study 4 assesses clinical pain, pain in response to palpation of muscles of mastication and the temporomandibular joint, psychosocial variables and hormonal status during each trimester of pregnancy, as well as postpartum in TMD cases and age-matched controls. Finally, Study 5 compares hormone levels, pain report and psychological factors over the menstrual cycle in women diagnosed with joint pain only and women diagnosed only with muscle pain. Thus, the proposed studies will: 1) provide important descriptive information concerning the course of clinical pain across the menstrual cycle and during pregnancy; 2) illuminate relationships between clinical pain, generalized pain sensitivity, psychological state, gender and hormonal status; and 3) explore whether central or peripheral mechanisms may be involved in pain-hormone relationships.